1. Basics
1.1. Unlimited Money Exploit
1.2. All Witcher Gear Set Locations & Showcase (With Upgrade Diagrams)

2. Collectibles
2.1. All Places of Power Bonuses (Power Overwhelming)
2.2. All Monster Nests (Pest Control)
2.3. All Bomb Type Formulae (Bombardier)
2.4. All Elements of one Set of Witcher Gear (Armed and Dangerous)

3. Story-Related
3.1. Friends With Benefits (Mission: An Invitation from Keira Metz)
3.2. Kingmaker (Mission: Possession)
3.3. Full Crew (Mission: The Isle of Mists)
3.4. Assassin of Kings (Mission: Reason of State)

4. Miscellaneous
4.1. Butcher of Blaviken – Kill at least 5 opponents in under 10 seconds
4.2. Can’t Touch This! – Kill 5 foes in a fight without taking damage
4.3. Triple Threat – Kill 3 opponents in one fight using 3 different methods
4.4. Fist of the South Star – Defeat an opponent in a fistfight without taking damage
4.5. What Was That? – Attack, counter, cast a Sign and throw a bomb in under 4 seconds
4.6. Kaer Morhen Trained – Perform 10 counterattacks in a row without getting hit
4.7. Humpty Dumpty – Kill 10 enemies by knocking them off somewhere high with the Aard
4.8. That Is the Evilest Thing… – Ignite gas from Dragon’s bomb using a burning enemy
4.9. Brawler – Defeat Olaf, the Skellige champion of unarmed combat
4.10. Overkill – Make 10 opponents suffer from bleeding, poisoning and burning simultaneously

5. Side Quests
5.1. Brawl Master – Complete all fistfighting quests in Velen, Skellige and Novigrad
5.2. Gwent Master – Defeat Tybalt at the gwent tournament held at the Passiflora
5.3. Fast and Furious – Win all the horse races in the game
5.4. Shrieker – Complete the contract on the shrieker
5.5. Fearless Vampire Slayer – Complete the contract on Sarasti
5.6. Woodland Spirit – Complete the contract on the Woodland Spirit
5.7. Fiend or Foe? – Complete the contract on Morvudd
5.8. Ashes to Ashes – Complete the contract on Therazane
5.9. The Doppler Effect – Resolve the doppler problem in Novigrad

6. DLC – Hearts of Stone
6.1. Rad Steez, Bro! – Complete all fistfighting quests in Velen, Skellige and Novigrad
6.2. Moo-rderer – Defeat Tybalt at the gwent tournament held at the Passiflora
6.3. Return to Sender – Win all the horse races in the game
6.4. When It’s Many Against One… – Complete the contract on the shrieker

7. DLC – Blood and Wine

Unlimited Money Exploit
This exploit / glitch allows you to make 1000 crowns per minute in The Witcher 3 Wild Hunt. You must buy shells from a merchant, dismantle them and then sell the pearls for a higher price. It works like this:

Step 1: Go to the merchant at Hierarch Square in Novigrad. Buy all his Shells and Sea Shells. Now exit the shop and talk to the merchant again, he will have all shells in stock again! Buy as many as you can. Tip: Once you reach Velen you can swim directly to Novigrad or take a boat to get there.
Step 2: Go to the armorer right next to the merchant. Dismantle the Shells to get pearls.
Step 3: Sell the pearls to the armorer until he runs out of money.
Step 4: Meditate for 5 days and the armorer will have roughly 1000 coins again. Sell pearls to him again.
Step 5: Repeat as many times as you want.

Buying and dismantling a Shell costs 8 coins. Selling the pearl you get from it gives you 109 coins! That’s 101 coins profit per shell!
You can keep doing this for however long you want. Should the merchant not have shells in stock you need to meditate or fast travel to another map, then check again.
Also make sure you are doing this at daytime. Merchants and armorers aren’t around at night.

Witcher Gear Sets
There are 4 Witcher Sets in the game: Serpentine, Griffin, Feline, Ursine. They are the best armor and weapon sets available and are a huge advantage when playing on Death March difficulty (and they look pretty awesome, too).
The Serpentine set consists of only two swords and is found in White Orchard. The Griffin Set (medium armor) is found in Velen, the Feline Set (light armor) in Novigrad and the Ursine Set (heavy Armor) in Skellige.
They have 4 tiers each: Normal, Enhanced, Superior, Mastercrafted. You must collect the upgrade diagram and take them to a blacksmith and armorer to upgrade your sets.

The Playlist below shows all their locations, including the upgrade diagram locations!

Also, if you want a sneak peek at what those sets look like you can find a video for all of them right here:

Power Overwhelming
Have all possible Place of Power bonuses active at the same time.
Places of Power are ritual stones hidden in the woods of the White Orchard Map (that’s where the game starts). They are marked with question marks on the map until you have discovered them. Activating the places of power will earn you a skill point and give you a significant boost for one of your signs. You have 5 signs, so you need to activate the 5 corresponding stones. One for each sign.
The catch is that the effect only stays active for 30 minutes. That means you have to activate all stones in quick succession. But no worries, there’s more than enough time and you can make use of fast travel if you wish.

Pest Control
Destroy all monster nests in the Velen / Novigrad region, or in Skellige.
It’s recommended you do this on Skellige as it has the fewest monster nests, making it the quickest way to earn this trophy or achievement (Velen/Novigrad has over 20).
4 of the Skellige Monster Nests are on the main island (Ard Skellig) and 1 on the northern island (An Skellig). This video starts in the south and ends in the north. You must have bombs in your inventory to destroy the nests.

Bombardier
Collect the formulae for 6 different bomb types.
You can simply buy 6 bomb formulae from a herbalist to unlocks this trophy / achievement. There’s one at the “Herbalist’s Hut” fast travel point in the south-east of Novigrad. He offers 8 different bomb formulae. This will cost you around 2000 crowns. You can simply create a backup save before doing this and sell all your crafting materials / alchemy ingredients to the merchant, then buy the formulae with the money. Reload your save game to get the money back.

Armed and Dangerous
Find and equip all the elements of one set of witcher gear.
The Griffin Witcher Gear Set can be found in Velen (Scavenger Hunt: Griffin School Gear). It consists of 6 pieces. Finding, crafting, and equipping all of them will unlock the Armed and Dangerous trophy / achievement. You can craft them at the armorer and blacksmith in Oxenfurt (big town in the east of Novigrad). To get the required materials you should loot all monsters you kill during story missions and side quests. Some materials need to be crafted from other components or you must dismantle a weapon. For example to get silver ingot you could dismantle one of your silver swords at the blacksmith.

After equipping all 6 pieces you will receive the trophy / achievement.

Friends With Benefits
Complete the subplot involving Keira Metz.
To do this you must first complete the main story quests Hunting a Witch, Wandering in the Dark, Magic Lamp! In these quests you will go through a dungeon with Keira (unmissable). After this story questline is complete you will automatically receive a new side quest called “An Invitation from Keira Metz”. Go visit Keira in her hut in the woods of Velen to start this optional subplot.
It consists of multiple small side quests:

1. An Inivtation from Keira Metz (0:05)
2. A Towerful of Mice (0:54)
3. A Favor for a Friend (8:28)
4. For the Advancement of Learning (14:40)

Be sure to track the quests so you can see where to go next. Complete these 4 quests and you will receive the Friends With Beneifts trophy / achievement at the end. It’s highly recommended that you send Keira to Kaer Morhen at the end and not kill her (required for “Full Crew” trophy).

Kingmaker
Complete the subplot about choosing Skellige’s ruler.
To do this you must first complete the main story quest “The King is Dead – Long Live the King”! That’s the first main quest on The Skellige Isles. After that you will automatically receive two new side quests called “Possession” and “The Lord of Undvik” (cannot be missed). You can mark them in the side quests tab in your inventory.
The subplot about Skellige’s ruler consists of multiple side quests:

1. Possession (0:05)
2. The Lord of Undvik (16:43)
3. King’s Gambit (26:29)
4. Coronation (36:18)

As soon as Possession and The Lord of Undvik are complete you will automatically receive the next quest “King’s Gambit”. In this quest you have to choose during a dialogue whether to go with Cerys or Hjalmar (29:46 in video). This will decide who becomes the ruler! It’s also extremely important for the Full Crew trophy / achievement. If you don’t help either of them you will miss the Full Crew trophy. So be sure to help either Cerys or Hjalmar, it doesn’t matter which one.

Full Crew
Bring all possible allies to Kaer Morhen for the battle against the Hunt.
This trophy / achievement is HIGHLY MISSABLE!!!
There are 7 allies that you must recruit for the Full Crew. After doing the main quests in Kaer Morhen (towards the end of the story) you will receive a main mission called “The Isle of Mists” and 4 other “Brothers in Arms” quests. That’s when you are supposed to recruit people for your upcoming battle in Kaer Morhen. You must play a series of lengthy side quests and subplots to recruit everyone, which is going to take several hours. Keira Metz and Triss can be recruited before reaching this point in the game and are the easiest to miss.

You need to recruit the following Allies:
+ Keira Metz (0:05, Velen, send her to Kaer Morhen at the end of her subplot instead of killing her. Her subplot consists of the side quest “An Invitation from Keira Metz”, “A Towerful of Mice”, “A Favor for a Friend”, “For the Advancement of Learning”. Full walkthrough: https://www.youtube.com/watch?v=gLJQ3cfvEbU)
+ Triss Merigold (2:08, Novigrad, complete her subplot. It starts with the side quest “A Matter of Life and Death” and ends with “Now or Never”. During Now or Never you must choose during the dialogue at the harbor that you want her to stay and that you love her. She will then go to Kaer Morhen automatically after a cutscene)
+ Roche (3:52, Novigrad, complete side quest “An Eye for an Eye”, then talk to Roche during Main Story Mission “Brothers in Arms: Novigrad” and he will come to Kaer Morhen)
+ Ves (3:52, Novigrad, complete side quest “An Eye for an Eye”, then talk to Roche during Main Story Mission “Brothers in Arms: Novigrad” and he will bring Ves with him)
+ Zoltan Chivay (5:05, Novigrad, simply talk to him during Main Story Mission “Brothers in Arms: Novigrad”)
+ Ermion (5:35, Skellige, simply talk to him during Main Story Mission “Brothers in Arms: Skellige”)
+ Hjalmar (6:08, Skellige, complete the subplot about choosing Skellige’s ruler for the Kingmaker trophy. The subplot consists of the side quests “Possession”, “The Lord of Undvik”, “King’s Gambit”. During King’s Gambit you must choose to help either Hjalmar or Cerys, doesn’t matter which one. Then talk to them once they are ruler and Hjalmar will come with you. Full walkthrough: https://www.youtube.com/watch?v=URs1yUckjec)

There are other characters you can talk to during the Brothers in Arms quests. Also some that can be recruited from side quests, but they are optional and have no impact on the trophy or achievement. It doesn’t matter if they die or whether you talk to them or not. Feel free to skip them all. Cerys an Craite is only important if she becomes ruler of Skellige, then you must talk to her.

These characters are NOT needed.
– Emperor Emhyr Var Emreis (Royal Palace of Vizima)
– Letho (Velen)
– Sigismund Dijkstra (Novigrad)
– Folan (Skellige, during side quest “The Lord of Undvik”)
– Vigi (Skellige, during side quest “The Lord of Undvik”)
– Crach an Craite (Skellige)
– Cerys an Craite (Skellige, should she become ruler of Skellige you need to talk to her and she will send Hjalmar to Kaer Morhen)

THINGS THAT COULD GO WRONG / WHAT IS MISSABLE:
– You could end up killing Keira Metz if you make wrong dialogue choices at the end of her subplot
– Triss Merigold will sail away and never return if you don’t tell her to stay and that you love her at the end of her subplot
– If you choose the third dialogue choice during the King’s Gambit quest of the Kingmaker subplot you will walk away and neither Hjalmar, nor Cerys will become ruler. Then Hjalmar cannot be recruited anymore.
– You could ignore the Brothers in Arms story quests entirely and go directly to the Isle of Mists, thus missing all possible allies

Assassin of Kings
Take part in the assassination of King Radovid.
This trophy / achievement is HIGHLY MISSABLE!!!
You have to do a series of lengthy side quests to trigger the “Reason of State” side quest at the very end of the game. During “Reason of State” you will then automatically assassinate King Radovid as part of the quest.
If you miss one of the required side quests before going to the Isle of Mists you cannot trigger “Reason of State” anymore. If you make a wrong dialogue choice during the “Blindingly Obvious” main story quest you will miss it, too. Be sure to always choose the first dialogue option at the end of this quest when talking to Dijkstra and Philippa.

The necessary quests are all found in Novigrad. They are as follows:

1. Redania’s Most Wanted (0:05)
2. An Eye for an Eye (0:49)
3. A Matter of Life and Death (1:30)
4. Now or Never (2:23)
5. A Deadly Plot (3:22)
6. [Main Quest] Blindingly Obvious (4:40 – must always choose first dialogue choice at end of quest when talking to Dijkstra and Philippa)
7. Reason of State (7:10)

Be sure to do them as soon as they become available to you. The exact requirements to trigger each of those side quests are shown during the video (click on the time links).

Butcher of Blaviken
Kill at least 5 opponents in under 10 seconds.
A great place to get the two trophies / achievements “Butcher of Blaviken” and “Can’t Touch This!” is at the Hanged Man’s Tree Fast Travel Point on the Velen Map. That’s the point in the middle of the map where you enter Velen for the very first time. Near the fast travel point there’s a pack of level 1 wolves. Block their attacks until they are all in front of you, then use the Igni sign to kill them instantly.
When holding down the block-button they cannot hurt you. If there are only a few wolves left you can take them out with some quick attacks.

Be sure to create a save game before trying this. In case you fail you can reload your save game and try again. You can also make the wolves respawn by fast traveling to another map (away from Velen).

Can’t Touch This!
Kill 5 foes in a fight without taking damage (except for Toxicity) and without using the Quen Sign.
A great place to get the two trophies / achievements “Butcher of Blaviken” and “Can’t Touch This!” is at the Hanged Man’s Tree Fast Travel Point on the Velen Map. That’s the point in the middle of the map where you enter Velen for the very first time. Near the fast travel point there’s a pack of level 1 wolves. Block their attacks until they are all in front of you, then use the Igni sign to kill them instantly.
When holding down the block-button they cannot hurt you. If there are only a few wolves left you can take them out with some quick attacks.

Be sure to create a save game before trying this. In case you fail you can reload your save game and try again. You can also make the wolves respawn by fast traveling to another map (away from Velen).

Triple Threat
Kill 3 opponents in one fight using 3 different methods (swords, bombs, crossbow, Signs, etc.).
Can easily be done at the “Hanged Man’s Tree” fast travel point in Velen (middle of the map). By the time you enter Velen you will automatically have a crossbow in your inventory. Equip the crossbow and Igni sign. Now kill some wolves near the fast travel point with the Igni sign, then use your sword until only one is left. Kill the last one with your crossbow (press R1 on PS4 / RB on Xbox to shoot).
The trophy / achievement pops after the fight is over and all enemies are dead.

Fist of the South Star
Defeat an opponent in a fistfight without taking any damage.
You can find a fistfight at the “Inn at the Crossroads” fast travel point on the Velen map. Go into the inn and there will be some men fighting in the corner. Talk to them to participate. When the fight starts you must immediately hold down the block-button. After blocking your opponent’s strikes you use strong attacks (PS4: triangle / Xbox: Y) to break his defense and take him out.

What Was That?
Attack, counter, cast a Sign and throw a bomb (in any order) in under 4 seconds.
First you need to craft a bomb with alchemy. The necessary ingredients can be bought from herbalists (there’s one in the middle of White Orchard). Put the bomb in your inventory and look for an enemy. But make sure it’s not a very weak enemy as you may one-hit kill it. Start with the counter attack, followed by a quick attack, throw the bomb and cast the sign at the end.
Don’t forget to select the bomb in your weapon wheel before the fight.

Kaer Morhen Trained
Perform 10 effective counterattacks in a row without getting hit or parrying.
This works best against human city guards with swords. Archers are also perfect as they always carry a sword. Look for a single city guard and counter 10 attacks in a row. You must press the block-button (L2 on PS4 / LT on Xbox) just before the enemy is about to hit you. Always press the block-button when the enemy has his sword vertically in the air above his head (a fraction of a second after he starts swinging the sword and a fraction of a second before he hits you). Your timing needs to be spot-on and it’s gonna take a few tries.
Best place to do this is by the river, north of the Woesong Bridge fast travel point on the White Orchard map (first town you enter in the game). There’s a friendly archer here. Attack him to start the fight. Doing it against friendly guards is great as they will only knock you out and not kill you. So if you mess up you will respawn right in front of the archer without any loading times and can keep trying.

Humpty Dumpty
Kill 10 opponents by knocking them off somewhere high with the Aard Sign.
A great place to do this is the Bandit Camp at the Devil’s Pit fast travel point in Velen. There’s a huge Bandit Camp here. Lure some bandits to a ledge, preferrably the one shown in the video where you enter the camp. Block or counter their attacks to push them to the edge, then immediately use the Aard sign to knock them down the hill. Kill the enemies with two-handed weapons / axes with your sword, rather than the Aard sign. Their attacks cannot be countered and they don’t usually fall off the ledge, so they are only in your way. Once all enemies are dead you fast travel to the Royal Palace of Vizima map and return to the Devil’s Pit. All bandits will have respawned and you can try again. You should be able to get 4-6 kills per run.
You don’t have to buy any skill upgrades to do this.

That Is the Evilest Thing…
Ignite the gas produced by a Dragon’s Dream bomb using a burning opponent. Do this 10 times.
First you must buy the formula for the Dragon’s Dream Bomb from the Herbalist in the east of Novigrad. He also has the required ingredients in stock. Buy them and craft the bomb. Now look for a group of monsters or humans without armor. Use Igni on them to make them burn, then immediately throw the Dragon’s Dream Bomb on the burning enemy. This will ignite the gas produced by the bomb and cause an explosion. You must repeat this 10 times for the trophy / achievement to unlock.
If you have strong alcohol in your inventory you can meditate to replenish your bombs. Fast travel to another map (e.g. Royal Palace of Vizima) to make enemies respawn, or do it against different enemies every now and then if you don’t want to farm it in one spot (can also be combined nicely with destroying monster nests).

Brawler
Defeat Olaf, the Skellige champion of unarmed combat.
To fight Olaf you must first complete the other 3 fistfights on The Skellige Isles. The first one is in Kaer Trolde Harbor (town in the north of main island), the second in Arinbjorn (far west on the main island) and the third in Harviken (small island in the south-east of the map). The fight against Olaf then takes place on Urialla Harbor (small island in the north of the map). Go to the arena to start the fight. Now dodge Olaf’s attacks (PS4: Circle / Xbox: B) and throw 2-3 heavy punches at him before you dodge again. The trophy / achievement will pop when you finish the dialogue after the fight.

Overkill
Make an opponent suffer from bleeding, poisoning and burning simultaneously. Do this 10 times.
A sure shot way to get this trophy / achievement is to use Broadhead Bolts (bleeding), Devil’s Puffball Bombs (poisoning) and Dancing Star Bombs (burning). The Broadhead Bolts are available at most blacksmiths and have a 100% bleeding chance (each shot will always make enemies bleed for 15 seconds). The Devil’s Puffball creates a poison cloud and the enemy must be standing inside the cloud to receive poison damage. The Dancing Star Bomb does burning damage and has a much higher chance of burning enemies than Igni (but it’s possible with Igni). The two bomb formulae can be bought at the Herbalist’s Hut in Novigrad.
Once you have all these things head to the Devil’s Pit Bandit Camp in Velen. Be sure to set the difficulty to Death March, otherwise they will die too quickly. Start by shooting the broadhead bolt, followed by the Devil’s Puffball and then the Dancing Star Bomb. Stay very close to enemies so that they can’t run away from the poison cloud. The three effects must be active on one enemy at the same time. Repeat 10 times. You can meditate to replenish your bombs. Fast travel to another map to make the bandits respawn.

You can also do this against most other human enemies, animals and several monster types. Some enemies are resistant to some of the three required effects, so not all enemies will work! Bandits, Bears, Wolves, Cyclopes and anything else without armor works best.

Brawl Master
Complete all fistfighting quests in Velen, Skellige and Novigrad.
There are 14 fistfights that you must win to unlock the Brawl Master trophy / achievement. After winning a fight you will receive a fistfighting questline for that region. You can then track this side quest to see the next fight highlighted on the map. It doesn’t matter in what order you do the first 3 fights of each map. But the fourth fight (champion) is only unlocked after the other 3 fighters have been defeated.
The fights get increasingly harder with every map. If you have too much trouble, then lower the difficulty in the game options. The basic strategy for every fight is to counter (or dodge) an opponents attack, then use 3 quick strikes to hurt him.

The fights will become available after completing the “Bloody Baron” main story quest in Velen. Just walk up to the Bookie to start fighting. If you lose a fight you can replay it by talking to the Bookie again (or load last checkpoint). Unlocking the very last fight requires you to complete a side quest to get rid off a wraith that haunts the arena. Let the wraith defeat you in combat and talk to the guards in the watchtower near the arena to unlock the last fight. If you die against the champion of champions you need to reload the last save game to try again.

Gwent Master
Defeat Tybalt and win the gwent tournament held at the Passiflora.
This trophy / achievement is MISSABLE!!!
Be sure to create a save game between each match and before starting the tournament. If your deck is too weak and you lose a match it will fail the quest. The only way to retry is to load an older save game.
First you must build a very strong deck of Gwent Cards and then go to the Passiflora (brothel) in the north of Novigrad. Here you can talk to a person in the back of the Passiflora with a side quest marker. Pay the 1000 Crowns fee to participate and the “High Stakes” side quest will start. You must defeat 4 very strong gwent players to finish the quest.
You can win with any deck, but the Northern Realms deck is highly recommended due to its many spy cards. You may want to wait and work towards the Card Collector trophy first before attempting this. By the time you reach the tournament you will already have learned how Gwent works. While collecting the best available cards you will in all likelihood earn “Geralt and Friends” and “All In” naturally without even trying.
Below are the locations of all gwent cards used in this video:

My deck of cards (Northern Realms, total of 22 Unit cards and 5 Special Cards):
3x Commander’s Horn (buy from merchants at Passiflora, Velen Inn at the Crossroads, Oxenfurt Alchemy Inn)
2x Scorch (buy from merchants at Kaer Trolde Inn, Oxenfurt Alchemy Inn)
1x Geralt of Rivia (Gwent: Old Friends, from Thaler)
1x Cirilla Fiona Elen Riannon (Gwent: Big City Players, from merchant in the woods)
1x Yennefer of Vengerberg (Gwent: Playing Inkeeps, from Oxenfurt innkeeper)
1x Vesemir (Gwent: Big City Players, from Vivaldi banker)
1x Zoltan Chivay (randomly earned, can be replaced with any other card)
1x Dandelion (Side Quest: A Matter of Life and Death, win match at masquerade ball)
1x Mysterious Elf (Gwent: Skellige Style, from Alchemist after doing his side quest)
1x Vernon Roche (Gwent: Velen Players, beat the player in Midcopse)
1x John Natalis (Side Quest: A Dangerous Game)
1x Esterad Thyssen (Gwent: Big City Players, from Dijkstra)
1x Catapult (buy from merchant at Passiflora)
1x Dethmold (automatically in your deck from the beginning of the game)
2x Trebuchet (automatically in your deck from the beginning of the game)
1x Ballista (automatically in your deck from the beginning of the game)
1x Ves (automatically in your deck from the beginning of the game)
1x Prince Stennis (automatically in your deck from the beginning of the game)
1x Dun Banner Medic (automatically in your deck from the beginning of the game)
1x Sigismund Dijkstra (Gwent: Velen Players, from Bloody Baron at Crow’s Perch)
2x Blue Stripes Commando (buy from merchants at Crow’s Perch and Midcopse)
1x Thaler (buy from Arinbjorn innkeeper in Skellige)

The must-have / most important cards are: Geralt of Rivia, Cirilla Fiona Elen Riannon, Yennefer of Vengerberg, Mysterious Elf, Dun Banner Medic, Thaler, Commander’s Horn.

Strategies:

– Always play your spy cards first. Yes, they will add some points to your opponent’s score, but you can draw 2 more cards. Don’t be afraid to lose the first round if it means you will have 14 cards and your opponent only has 8 cards left. This guarantees a certain win, as your enemy doesn’t have enough cards to keep up with you.

– Keep your deck to the minimum of 22 unit cards and throw out as many special cards as possible. This increases the chance of drawing only your best cards. Keep some Commander’s Horn cards.

– The final player uses a Monster deck which focuses almost entirely on Close Combat. Be sure to have 2 Biting Frost cards and some Scorch Cards in your deck. As long as you can play a Biting Frost card your opponent won’t stand a chance.

Fast and Furious
Win all the horse races in the game.
There are 11 horse races that you need to win to earn the Fast and Furious trophy / achievement. 3 in Velen, 4 in Novigrad, 4 in Skellige. It’s recommended you do them in the order shown in this video as some races can only be played if you won certain other races already. The ones in Velen are all at the same location and the track is the exact same. The first 3 of Novigrad are also in the same place, but each one has a different track. Keep talking to the quest giver to ride against the other opponents. The ones on Skellige all have their own unique location.
Doing horse races is well worth your time! The saddlebags you earn will let you carry up to 160 items in your inventory, the racing saddles will give your horse more stamina, and with the blinders your horse won’t get frightened by monsters so quickly. You will also earn a great deal of money for very little work (the 7th race alone gives you 700 coins and takes only 3 minutes). It’s a good way to get some cash early in the game.

Shrieker
Complete the contract on the shrieker.
The Shrieker contract starts at the quest board in Crow’s Perch (Velen Map). Make sure you are tracking the quest to see where you must go. Talk to the man down by the village and accept his offer. Ask the child behind the house about the Shriker and head to the target area. Investigate the site to find some blood trails. Follow the blood, go into the cave and throw a bomb at the Shrieker’s nest to lure it out. Now kill the Shirker outside the cave and return to the man in the village to collect your reward.

Fearless Vampire Slayer
Complete the contract on Sarasti.
For this trophy / achievement you must complete the “The Mystery of the Byways Murders” witcher contract (Recommended level: 22+). It can be started at the Notice Board in Oreton, a village in the western half of Velen. From the notice board you must pick up the note that says “Contract: Missing Soliders”.
Talk to the commander in the village and travel to Byways further south. Here you must kill 5 ghouls which is the hardest part of the quest. After they are dead you talk to the villagers and follow some clues to reach the catacombs below the village. Here you must fight Sarasti, a Vampire boss. It’s a relatively easy fight. When you attack with quick strikes it will stagger Sarasti, giving him no chance to attack you. He has relatively low health too, so this fight shouldn’t last long.

Talk to the villagers after slaying the monster and the trophy / achievement will unlock.

Woodland Spirit
Complete the contract on the Woodland Spirit.
For this trophy / achievement you must play the “In the Heart of the Woods” Side Quest (Recommendend Level: 22+). In can be started in Farylund, a small village on the main island of Skellige. Go into the woods and you will run into some villagers. This will automatically begin the quest. Investigate the marked areas in the woods and then look at the Woodland Spirit entry in your Bestiary to continue the quest.
The important thing is that you accept Sven’s offer who wants you to kill the Woodland Spirit (the younger man) and not the offer from Harald (the elderly man). If you go with Harald’s offer you won’t get to fight the Woodland Spirit and will miss this trophy!

The Woodland Spirit is one of the hardest bosses in the game. It has a lot of health and will kill you in 1-2 hits. Always activate the Quen Sign to protect yourself from damage. The boss is quite slow though. Attack it quickly when it appears, so it doesn’t get a chance to attack you first (and if it does your Quen Sign will protect you).
Before going into this fight you should get a silver sword with good damage stats and use Relict Oil on it for some bonus damage.

Remember: If you go with Harald’s offer you won’t get to fight the Woodland Spirit and will miss this trophy! You must talk to Sven instead!

Fiend or Foe?
Complete the contract on Morvudd
For this trophy / achievement you must play the “Contract: Missing Son” Side Quest (Recommendend Level: 29+). It can be started at the notice board in Rannvaig, a village on the main island of Skellige. The quest is fairly straight forward, yet no easy task at all. You must fight one of the strongest monsters in the game, called Morvudd. It will kill you in 1-2 hits and has quite a bit of health. You must also defeat it twice in a row, as it will run away the first time you fight it.
The basic strategy for this fight is to dodge Morvudd’s attacks to the left at all times, then use one single strong attack and repeat. This way you can keep going around the enemy in circles and if you get the timing down the boss will hardly ever hit you while you deal some devastating blows. Also use Relic Oil on your silver sword for bonus damage and bring some Samum bombs.
Keep your Quen Sign active at all times, otherwise you may get instant-killed by the enemy. Once you’ve defeated Morvudd for the second time you must investigate its lair and return to the quest giver. This will complete the Missing Son quest and unlock the trophy or achievement.

Ashes to Ashes
Complete the contract on Therazane.
You must complete the “Contract: Doors Slamming Shut” Side Quest to unlock this trophy / achievement (Recommendend Level: 24+). It can be started at the quest board on Hierarch Square in Novigrad. From the quest board you must pick up the note that says “Contract: Haunted House”. The “Doors Slamming Shut” witcher contract will then start automatically.
Go to the innkeep near the quest board and talk to the the man on the upper floor. He will send you to a mansion in Novigrad. Go to the basement and you will discover Therazane, a mighty elemental Boss Enemy. He will kill you in 2 hits and has an incredible amount of health for his level. He is resistant to almost everything. Always keep your Quen sign active.
The basic strategy for this boss fight is to attack Therazane with 1-2 strong attacks, then dodge back immediately when he starts an attack. He will miss you almost every time and if something goes wrong you still have your Quen sign to protect you from damage. Once you have learned his attack pattern the fight will be very doable, especially because he is a very slow enemy and easy to dodge. When you attack him too many times in a row he will go into a defensive positon. Don’t attack him when he does that! He will block your attack and cause a massive explosion that has the potential to one-hit kill you.

After Therazane is dead you must return to the quest giver to unlock the trophy / achievement.

The Doppler Effect
Resolve the doppler problem in Novigrad.
To unlock this trophy / achievement you must complete the side quest “An Elusive Thief”. It can be started at the quest board on Hierarch Square in Novigrad. From the quest board you must pick up the note that says “Contract: Imp”. The “An Elusive Thief” side quest will then start automatically.
Go to the market square at day and talk to the merchant. Now follow the red footsteps on the ground by using your witcher sense. You will reach a house where you must pick up a letter and read it in your inventory. Follow the trail of clues again and you will meet the Doppler. Defeat him and combat and you can choose to either kill him or let him go. If you let him go (which is the recommended solution) he will give you a lot of coins and a diagram. Return to the market square again to talk to the merchant and the trophy / achievement will pop.

Rad Steez, Bro!
Slide downhill uninterrupted for at least 10 seconds.
There are many mountains in Skellige where you can do this. A perfect spot is at the “Distillery” fast travel point in the east of Skellige’s main island. Save your game when you reach the fast travel point. Now slide down the hill and you should earn the trophy / achievement. In case something goes wrong you can load the last save game to be back up on the mountain for a retry.

Moo-rderer
Kill 20 cows.
You can farm this very quickly at “Martin Feuille’s Farmstead” (fast travel point) in the north of Novigrad. There’s a group of 10+ cows here. Kill them all and meditate for a day to make them respawn. Kill a few more and the trophy / achievement will unlock. If there are no cows when you arrive, meditate and they will spawn eventually.

Return to Sender
Kill 3 opponents with their own arrows.
First you must buy the “Arrow Deflection” skill (level 3/3) in the combat skill tree. Now you must look for some archers and parry their arrows just a moment before they hit you (L2 on PS4 / LT on Xbox One).
A great spot is at the eastern bridge of Oxenfurt. There’s a fast travel point and some archers on the bridge. After killing them you can meditate for an hour and they should respawn. Repeat until the trophy / achievement unlocks.

You are also allowed to weaken them with your sword. Only the final hit has to be from a deflected arrow.

When It’s Many Against One…
Provoke all Iris von Everec’s Nightmares into fighting you at the same time and defeat them.
This trophy / achievement is missable! The fight against the Nightmares takes place at the end of main quest “Scenes from a Marriage” after recreating the memory in the dining room.
You should create a manual save game before this fight. It’s also highly recommended to select the lowest difficulty in the gameplay options. When the fight starts one nightmare will be fighting you and 5 are standing still. Go around the room and hit each nightmare with one light attack to provoke them. If you hit them more than once they might die, so be careful!
If done correctly there will be a total of 6 nightmares fighting you at the same time. If you killed one already you must reload the last checkpoint. The quickest way to take them out is by using the Whirl skill. You can use any attack you want though.

Blood and Wine DLC Guide can be found here:
The Witcher 3 Blood and Wine Trophy Guide